Effect of boron ion implantation on the structural, optical and electrical properties of ZnSe thin films

Zinc Selenide (ZnSe) thin films were deposited onto well cleaned glass substrates using vacuum evaporation technique under a vacuum of 3×10⁻⁵ mbar. The prepared ZnSe samples were implanted with mass analyzed 75 keV B⁺ ions at different doses ranging from 10¹² to 10¹⁶ ions cm⁻². The composition, thickness, microstructures, surface roughness and optical band gap of the as-deposited and boron-implanted films were studied by Rutherford backscattering (RBS), grazing incidence X-ray diffraction, Atomic force microscopy, Raman scattering and transmittance measurements. The RBS analysis indicates that the composition of the as-deposited and boron-implanted films is nearly stoichiometric. The thickness of the as-deposited film is calculated as 230 nm. The structure of the as-deposited and boron-implanted thin films is cubic. It is found that the surface roughness increases on increasing the dose of boron ions. In the optical studies, the optical band gap value decreases with an increase of boron concentration. In the electrical studies, the prepared device gave a very good response in the blue wavelength region.     

Zn离子注入和退火对ZnO薄膜光学性能的影响

 利用溶胶凝胶方法在石英玻璃衬底上制备了ZnO薄膜，将能量56 keV、剂量1×10¹⁷ cm^-2的Zn离子注入到薄膜中。离子注入后，薄膜在500~900 ℃的氩气中退火，利用X射线衍射谱、光致发光谱和光吸收谱研究了离子注入和退火对ZnO薄膜结构和光学性质的影响。结果显示：衍射峰在约700 ℃退火后得到恢复；当退火温度小于600 ℃时，吸收边随着退火温度的提高发生蓝移，超过600 ℃时，吸收边随着退火温度的提高发生红移；近带边激子发光和深能级缺陷发光都随退火温度的提高而增强。     

Effects of post-annealing on structural, optical and electrical properties of Al-doped ZnO thin films

Aluminum-doped zinc oxide (AZO) films were deposited at 400 °C by radio-frequency magnetron sputtering using a compound AZO target. The effects of annealing atmospheres as well as hydrogen annealing temperatures on the structural, optical and electrical properties of the AZO films were investigated. It was found that the electrical resistivity varied depending on the atmospheres while annealing in air, nitrogen and hydrogen at 300 °C, respectively. Comparing with that for the un-annealed films, the resistivity of the films annealed in hydrogen decreased from 9.8 × 10⁻⁴ Ω cm to 3.5 × 10⁻⁴ Ω cm, while that of the films annealed in air and nitrogen increased. The variations in electrical properties are ascribed to both the changes in the concentration of oxygen vacancies and adsorbed oxygen at the grain boundaries. These results were clarified by the comparatively XPS analyzing about the states of oxygen on the surface of the AZO films. There was great increase in electrical resistivity due to the damage of the surfaces, when AZO films were annealed in hydrogen with a temperature higher than 500 °C, but high average optical transmittance of 80-90% in the range of 390-1100 nm were still obtained.     

Annealing effect on microstructure and mechanical properties of amorphous Al-C-N films

Al-C-N thin films with different Al contents were deposited on Si (1 0 0) substrates by closed-field unbalanced reactive magnetron sputtering in the mixture of argon and nitrogen gases. These films were subsequently vacuum-annealed at 700 °C and 1000 °C, respectively. The microstructures of as-deposited and annealed films were characterized by X-ray diffraction (XRD) and high-resolution transmission electron microscopy (HRTEM); while the hardness and elastic modulus values were measured by nano-indention method. The results indicated that the microstructure of both as-deposited and annealed Al-C-N films strongly depended on Al content. For thin films at low Al content, film delamination rather than crystallization occurred after the sample was annealed at 1000 °C. For thin films at high Al content, annealing led to the formation of AlN nanocrystallites, which produced nanocomposites of AlN embedded into amorphous matrices. Both the density and size of AlN nanocrystallites were found to decrease with increasing depth from the film surface. With increasing of annealing temperature, both hardness and elastic modulus values were decreased; this trend was decreased at high Al content. Annealing did not change elastic recovery property of Al-C-N thin films.     

Effects of high-dose Ge ion implantation and post-implantation annealing on ZnO thin films

This paper reports that ion implantation to a dose of 1×10¹⁷ ions/cm² was performed on c-axis-orientated ZnO thin films deposited on (0001) sapphire substrates by the sol-gel technique. After ion implantation, the as-implanted ZnO films were annealed in argon ambient at different temperatures from 600-900℃. The effects of ion implantation and post-implantation annealing on the structural and optical properties of the ZnO films were investigated by x-ray diffraction (XRD), photoluminescence (PL). It was found that the intensities of (002) peak and near band edge (NBE) exitonic ultraviolet emission increased with increasing annealing temperature from 600-900℃. The defect related deep level emission (DLE) firstly increased with increasing annealing temperature from 600- 750℃, and then decreased quickly with increasing annealing temperature. The recovery of the intensities of NBE and DLE occurs at \sim 850℃ and \sim 750℃ respectively. The relative PL intensity ratio of NBE to DLE showed that the quality of ZnO films increased continuously with increasing annealing temperature from 600 - 900℃.     

退火温度对Cr掺杂ZnO薄膜的微结构与机械性能的影响研究

本研究利用射频磁控溅镀法在玻璃基板上制备3 at.%的Cr掺杂ZnO薄膜,再以300℃～500℃温度退火处理25 mins,并探讨了退火温度对Al掺杂ZnO薄膜的微观结构与机械性能的影响.微观结构分析结果表明Cr掺杂ZnO薄膜的结晶方向为(002),且沿(002)方向的成长随退火温度升高而越加明显,但薄膜的表面却随退火温度升高而变得越来越粗糙.机械性能分析结果揭示晶粒尺寸随退火温度升高而增大,导致差排原子的动能随之降低,致使Cr掺杂ZnO薄膜的硬度随退火温度升高而增大,但对其对杨氏模量却没有太大的影响;此外,Cr掺杂ZnO薄膜的耐磨性与韧性均随退火温度升高而增强,表明退火处理对该薄膜的抗塑性形变能力有很大帮助.     

Ti离子注入和退火对ZnS薄膜结构和光学性质的影响

利用真空蒸发法在石英玻璃衬底上制备了ZnS薄膜,将能量80 keV,剂量1×10¹⁷ cm^-2的Ti离子注入到薄膜中,并将注入后的ZnS薄膜进行退火处理,退火温度500—700 ℃.利用X射线衍射（XRD）研究了薄膜结构的变化,利用光致发光（PL）和光吸收研究了薄膜光学性质的变化.XRD结果显示,衍射峰在500 ℃退火1 h后有一定程度的恢复;光吸收结果显示,离子注入后光吸收增强,随着退火温度的上升,光吸收逐渐降低,吸收边随着退火温度的提高发生蓝移;PL显示,薄 关键词： ZnS薄膜 离子注入 X射线衍射 光致发光     

The electrical properties of sulfur-implanted cubic boron nitride thin films

Cubic boron nitride (c-BN) thin films are deposited on p-type Si wafers using radio frequency (RF) sputtering and then doped by implanting S ions. The implantation energy of the ions is 19 keV, and the implantation dose is between 10 15 ions/cm 2 and 10 16 ions/cm 2 . The doped c-BN thin films are then annealed at a temperature between 400°C and 800 C. The results show that the surface resistivity of doped and annealed c-BN thin films is lowered by two to three orders, and the activation energy of c-BN thin films is 0.18 eV.     

The influence of substrate temperature on the morphology, optical and electrical properties of thermal-evaporated ZnTe Thin Films

The structural, morphological, optical and electrical properties of ZnTe films deposited by evaporation were investigated as a function of substrate temperature (at −123 and 27 °C) and post-deposition annealing temperature (at 200, 300 and 400 °C). It was determined that films deposited at both substrate temperatures were polycrystalline in nature with zinc-blende structure and a strong (1 1 1) texture. A small Te peak was detected in XRD spectra for both substrate temperatures, indicating that as-deposited ZnTe films were slightly rich in Te. Larger grains and a tighter grain size distribution were obtained with increased substrate temperature. Scanning electron microscopy (SEM) studies showed that the microstructures of the as-deposited films agreed well with the expectations from structure zone model. Post-deposition annealing induced further grain growth and tightened the grain size distribution. Annealing at 400 °C resulted in randomization in the texture of films deposited at both substrate temperatures. Optical spectroscopy results of the films indicated that the optical band gap value increased from 2.13 to 2.16 eV with increased substrate temperature. Increasing the annealing temperature sharpened the band-edge. Resistivity measurements showed that the resistivity of films deposited at substrate temperatures of −123 and 27 °C were 32 Ω cm, and 1.0 × 10⁴ Ω cm, respectively with corresponding carrier concentrations of 8.9 × 10¹⁵ cm⁻³ and 1.5 × 10¹⁴ cm⁻³. Annealing caused opposite changes in the film resistivity between the samples prepared at substrate temperatures of −123 and 27 °C.     

磷离子注入纳米金刚石薄膜的n型导电性能与微结构研究

系统研究了磷离子注入并在不同温度退火后的纳米金刚石薄膜的微结构和电学性能.研究表明,当退火温度达到800 ℃以上时,薄膜呈良好的n型电导.Raman光谱和电子顺磁共振谱的结果表明,薄膜中金刚石相含量越高和完整性越好,薄膜电阻率越低. 这说明纳米金刚石晶粒为薄膜提供了电导.1000 ℃退火后,薄膜晶界中的非晶石墨相有序度提高,碳悬键数量降低,薄膜电阻率升高.薄膜导电机理为磷离子注入的纳米金刚石晶粒提供了n型电导,非晶碳晶界为其电导提供了传输路径. 关键词： 纳米金刚石薄膜 n型 磷离子注入     

退火对B掺杂纳米金刚石薄膜微结构和电化学性能的影响

采用热丝化学气相沉积法制备B掺杂纳米金刚石薄膜,并对薄膜进行真空退火处理,系统研究了不同退火温度对B掺杂纳米金刚石薄膜的微结构和电化学性能的影响.结果表明,当退火温度升高到800 ℃后,薄膜的Raman谱图中由未退火时在1157,1346,1470,1555 cm^-1处的4个峰转变为只有D峰和G峰,说明晶界上的氢大量解吸附量减少,并且D峰和G峰的积分强度比I_D/I_G值变为最小,即sp²相团簇     

The effect of nitrogen ion implantation on tungsten surfaces

X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) were used to study the phase, composition and chemical states of elements at the tungsten surface. The measurement results indicate that nitrogen-containing phase of tungsten were formed by nitrogen ion implantation (energy 40 keV, implantation doses of 4×10¹⁷, 8×10¹⁷ and 1.6×10¹⁸ ions/cm²). The formation of the W_x(O,N) and WN in the surface layer occurred as a result of nitrogen ion irradiation. A decrease in concentration of W_x(O,N) is observed with increasing N⁺ while that WN increases. Due to residual oxygen in the chamber WO₃ still exists at the surface of the specimen.     

Effect of annealing on the optical and electrical properties of ZnO:Er films

The effect of dopant concentration and annealing in the oxidizing atmosphere on the structural, optical, and electrical properties of ZnO:Er films deposited on sapphire substrates by the electron-beam evaporation method is investigated. The optical and electrical properties of these films were studied by UV-VIS-IR absorption and reflection spectroscopy, photoluminescence, and resistivity measurements. Experimental results reveal that as-deposited ZnO:Er films have both high transmittance in the visible range and low electrical resistivity and can be used as efficient transparent conducting oxides (TCOs). These films annealed in the oxidizing atmosphere have a visible emission band which can be used to fabricate light-emitting diodes.     

氧离子注入纳米金刚石薄膜的微结构和电化学性能研究

在纳米金刚石薄膜中注入剂量为1012cm-2的氧离子,并进行700,800,900和1000?C的真空退火处理,系统研究薄膜的微结构和电化学性能结果表明,氧离子注入未退火(O120)和氧离子注入1000?C退火(O121000)电极的电势窗口分别为4.60 V和3.61 V,远大于其他电极的电势窗口,并且这两个样品的电极传质效率较高,说明氧离子注入和高温退火有利于提高电极的传质效率.红外光谱测试表明,样品O120和O121000的表面没有碳氢基团终止层,而其他样品均含有氢终止层,说明氧离子注入和高温退火破坏了薄膜表面含碳氢基团的氢终止层,提高了薄膜的电化学性能Raman光谱测试结果表明,金刚石含量较高、内应力较小和非晶石墨相无序化程度较大的样品具有较好的电化学性能;并且薄膜晶界处的非晶碳的团簇数量或者尺寸减小,样品的电化学性能提高.     

Analysis of the effect of annealing on the photoluminescence spectra of Cu ion implanted ZnS nanoparticles

In the present study, we report the photoluminescence (PL) study of nanoparticles of ZnS implanted with Cu⁺ ions at the doses of 5×10¹⁴, 1×10¹⁵ and 5×10¹⁵ ions/cm² and annealed at 200 and 300 °C. The photoluminescence spectra of the samples implanted at lower doses of 5×10¹⁴ and 1×10¹⁵ ions/cm² and annealed at 200 and 300 °C showed peaks at around 406, 418 and 485 nm. The PL emission peak at 485 nm was attributed to the transition of electrons from conduction band of ZnS to the impurity level formed by the implanted Cu⁺ ions. In the PL spectrum of the sample implanted at the highest dose of 5×10¹⁵ ions/cm², in addition to the emission peaks observed in the PL spectra of the samples implanted at lower doses, a peak at around 525 nm, the intensity of which decreased with increase in the annealing temperature, was observed. The emission peak at 525 nm was attributed to the transitions between sulfur and zinc vacancy levels. The full width at half maximum (FWHM) of the emission peak at 406 nm was observed to decrease with increase in annealing temperature, indicating lattice reconstruction. The observation of copper ion impurity related peak at 485 nm in the PL spectra of samples of the present study indicated that the doping of copper ions into the ZnS lattice is achievable by implanting Cu⁺ ions followed by annealing.     

Annealing effects on electrical and optical properties of ZnO thin films synthesized by the electrochemical method

Microstructural and electrical properties of potentiostatically electrodeposited ZnO thin films from an aqueous bath were investigated after annealing at different temperatures in Ar and 5% H₂/Ar atmospheres. It is confirmed that the bandgap energy of ZnO thin films decreased with annealing from 3.42 to 3.27-3.29 eV by calculating the wavelength of the absorption region. The annealing at temperatures as low as 200 °C decreased the sheet resistance of ZnO thin films because of the extinction of Zn(OH)₂ in the atmosphere. In addition, the sheet resistance of ZnO thin films decreased by annealing in a 5% H₂ atmosphere, which caused an increase of carrier concentration by hydrogen reduction.     

退火温度对硼掺杂纳米金刚石薄膜微结构和p型导电性能的影响

采用热丝化学气相沉积法制备硼掺杂纳米金刚石 (BDND) 薄膜, 并对薄膜进行真空退火处理, 系统研究退火温度对BDND薄膜微结构和电学性能的影响. Hall效应测试结果表明掺B浓度为5000 ppm (NHB) 的样品的电阻率较掺B浓度为500 ppm (NLB) 的样品的低, 载流子浓度高, Hall迁移率下降. 1000 ℃退火后, NLB和NHB 样品的迁移率分别为53.3和39.3 cm²·V^-1·s^-1, 薄膜的迁移率较未退火样品提高, 电阻率降低. 高分辨透射电镜、紫外和可见光拉曼光谱测试结果表明, NLB样品的金刚石相含量较NHB样品高, 高的硼掺杂浓度使薄膜中的金刚石晶粒产生较大的晶格畸变. 经1000 ℃退火后, NLB和NHB薄膜中纳米金刚石相含量较未退火时增大, 说明薄膜中部分非晶碳转变为金刚石相, 为晶界上B扩散到纳米金刚石晶粒中提供了机会, 使得纳米金刚石晶粒中B浓度提高, 增强纳米金刚石晶粒的导电能力, 提高薄膜电学性能. 1000 ℃退火能够恢复纳米金刚石晶粒的晶格完整性, 减小由掺杂引起的内应力, 从而提高薄膜的电学性能. 可见光Raman光谱测试结果表明, 1000℃退火后, Raman谱图中反式聚乙炔 (TPA) 的1140 cm^-1峰消失, 此时薄膜电学性能较好, 说明TPA减少有利于提高薄膜的电学性能. 退火后金刚石相含量的增大、金刚石晶粒的完整性提高及TPA含量的大量减少有利于提高薄膜的电学性能. 关键词： 硼掺杂纳米金刚石薄膜 退火 微结构 电学性能     

Microstructure and electrical properties of Mn-doped barium strontium titanate thin films prepared on copper foils

Ba_0.7−xSr_0.3Mn_xTiO₃ (x = 0, 0.025, 0.05) thin films have been prepared on copper foils using sol-gel method. The films were processed in an atmosphere with low oxygen pressure so that the substrate oxidation is avoided and the formation of the perovskite phase is allowed. XRD and SEM results showed that Mn doping enhanced the crystallization of the perovskite phase in the films. The Mn substitution prevents the reduction of Ti⁴⁺ to Ti³⁺, which is supported by XPS analysis. The Ba_0.7−xSr_0.3Mn_xTiO₃ film with x = 0.025 (BSMT25) exhibits preferred dielectric behavior and a lower leakage current density among the three thin films. The dielectric constant and loss of the BSMT25 film are 1213.5 and 0.065 at 1 MHz and around zero field, which are mostly desired for embedded capacitor applications. The mechanism of Mn doping on improving the electrical properties of barium strontium titanate (BST) thin films was investigated.     

Influence of annealing on the concentration profiles of boron implantations in silicon

The influence of annealing on the concentration profiles of boron implanted into silicon with does of 10¹⁴ ions/cm² up to 10¹⁶ ions/cm² and an energy of 70 keV was studied. The concentration profiles were measured with Secondary Ion Mass Spectrometry (SIMS). The broadening of the concentration profiles during annealing can be described as a superposition of effects resulting from a relatively immobile and a mobile boron fraction. The properties of the immobile boron fraction were studied by measuring the influence of a boron implantation on the distribution of a homogeneous boron background dope. From these experiments it was concluded that the immobile boron fraction consists of boron precipitates. The properties of the mobile fraction were studied from concentration profiles that were obtained after annealing during different periods at the same temperature. It was found that during the initial stage of the annealing process a fast broadening of the profile occurs; this was assumed to be due to an interstitial type boron diffusion. After prolonged annealing the much slower substitutional type diffusion prevails, due to trapping of the interstitial boron atoms by vacancies. The reliability of the SIMS method, as applied to profile measurements, was checked for the high boron doses used in this investigation. Excessive boron precipitates, obtained after annealing of a high dose, such as 10¹⁶ ions/cm² at about 1000°C, appear to give some increase of the ion yield.     

Fe纳米颗粒嵌埋对类金刚石薄膜结构及电学性能的影响

 采用脉冲激光气相沉积方法制备了不同Fe嵌埋浓度的Fe: DLC多层纳米复合薄膜。用X射线光电子能谱仪(XPS)对薄膜的组成成分进行分析。利用透射电子显微镜（TEM）、拉曼光谱、电流-电压曲线研究Fe纳米颗粒嵌埋对薄膜的微观结构及电学性能的影响。XPS和TEM表明,Fe纳米颗粒周期性地均匀地嵌埋在碳薄膜中。拉曼光谱表明薄膜中的C为典型的类金刚石结构,Fe纳米颗粒促进芳香环式结构的形成,薄膜结构的有序度提高。电流 电压曲线表明,Fe纳米颗粒的嵌埋导致薄膜的室温电导率增加。